As is known, conveyors, such as for example belts and the like, which support material so as to move it along a working surface, are widespread.
Usually, the movement of the conveyor must be monitored carefully so as to be able to know exactly the position in which the conveyor is, in order to be able to perform the desired processes on the material being transported by the conveyor.
Generally, the movements of the conveyor are not performed in a precisely controlled manner by the movement elements due to construction reasons, due to distortions caused by the elasticity of the conveyor or by the progressive wear thereof, or also due to the fact that the movement of the conveyor is performed manually on the worktable in free directions.
A known solution that allows the precise detection of the position of the conveyor is to provide on the conveyor, such as for example a belt, a regular grid, and preset an optical detection system that makes it possible to detect the offsets of the elements of the grid after each movement, with respect to the expected position, which is indicated by the movement means. In other words, the movement means move in theory the belt by a given position, and the detection systems, by detecting the grid defined on the belt, can determine whether the movement indicated by the movement means has occurred precisely, or whether the movement is instead different from the desired one set by the movement means.
The method cited above, however, is expensive, since it requires great precision in the geometry of the grid defined on the belt, and it is difficult to provide and has poor repeatability in conditions of exposed wear to which the belt is subjected, indeed because the grid tends to undergo deformations that can give rise to false readings.